Spectrum analyzers display the amplitude of an input signal versus frequency. Typically the frequency extends along the X-axis and the amplitude extends up the Y-axis of the display. They are used to measure the spectrum of an unknown signal within the frequency range of the particular analyzer ...

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28 views

Quantifying white noise with a spectrum analyzer

The setup of my problem is as follows. I have an experiment in which I want to apply a noisy voltage with a white (flat) spectral density over a large frequency range, say 0 to 7 GHz for example. Not ...
0
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1answer
31 views

Lock-in amplifier output to spectrum analyzer

In several lock-in amp tutorials and experiments (including at the end of “Physics 111: Low Light Signal Measurements” on Youtube), the lock-in amp X or Y output is applied directly to a spectrum ...
-4
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1answer
81 views

Circuit symbol for spectrum analyzer

Does anybody know what the circuit symbol for spectrum analyzer is? My internet searches for it haven't turned up anything so far. Most of the searches ended up showing the internal circuit diagram ...
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0answers
34 views

Impedance Spectroscopy - Modelling a physical system as an RC network

I have a physical system which can (in principle) be modeled as a network of resistors and capacitors. To extract values of components, I am doing a frequency sweep and Fourier transforming, and ...
1
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1answer
142 views

How to build an Audio Spectrum Analyzer/Sensor?

I am designing a smart RGB LED strip driver based on a Raspberry Pi and an Ardunio. The Ardunio would controll the LED strip, and other LEDs connected to a shift register, while the RPi would manage ...
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2answers
50 views

Affordable way to test frequency range of a 2.4GHz device [closed]

Does anyone know of a good/affordable way to test the frequency range of a RF device (e.g., Bluetooth module)? Not spectrum analysers since they're rather unaffordable. Are there relatively affordable ...
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2answers
44 views

Type of Wideband Transformer for Measuring 120 V AC signal + EMI

I'm looking to measure line EMI on a standard 120 V AC power circuit using some kind of transformer or other sensor. The device I'll be using to measure the waveform is an Ettus Research USRP N210, ...
0
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1answer
138 views

Detecting 2.4 GHz signals using oscilloscope [duplicate]

I have used a spectrum analyzer with an antenna to see packets at 2.4 GHz being transmitted from my transceiver successfully. There was a mode in the spectrum analyzer which helps you to take a look ...
0
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1answer
79 views

How to build a transmitter using a VCO module

this question is the consequence of my previous questions, since I am learning how RF transmitters works. In past I have also built some oscillators (using little transistors and a bunch of ...
1
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1answer
117 views

how to get wave formula using IFFT

I have a wave and i can't know its formula so i used Fast Fourier Transform (FFT) to make frequency spectrum for this wave to get all frequencies and amplitudes (in db) of this wave. [1] i need to ...
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1answer
91 views

7W IC amplifier

I have a 7W Audio Amplifier IC Module. It's instruction says power input should be 12~16 Volts. The audio source should be connected to "IN" and "G". Output should be a 7W Speaker to "SPK". In lab, ...
0
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1answer
98 views

Usefulness of VBW in spectrum analyzer

Typically in the block scheme of a spectrum analyzer a video filter, with a bandwidth VBW, is located after the envelope detector and before the screen. As pointed out in this document, the VBW may ...
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1answer
110 views

Vector Network Analyzer - The effect of increasing the number of measurement points

Does increasing the number of measurment points make the measurement time longer? RBW value does change the time, but does sweep bother the time of taking a single sample? I'm looking for ...
0
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2answers
293 views

What Language should I use for automated testing? [closed]

I'm the Lab Manager for a small company in the RF industry and I've recently been asked by our engineer to find a more "up-to-date" programming option for automating my bench testing/calibration ...
2
votes
1answer
683 views

How to conduct “Transient Power” measurement according to ETSI EN 300 220-1 (v2.4.1)?

Background Info The company I work for builds Active RFID hardware that needs to conform to the regulations defined in ETSI EN 300 220 (Part 1). Our working frequency is 433.92 MHz. I am responsible ...
3
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1answer
159 views

40 GHz spectrum analyzer with N-type coax input?

We have an old Rohde & Schwarz FSEK 30 that is advertised as having a range from 20 Hz to 40 GHz, with an N-type input connector. My conundrum is that a type-N connector with air dielectric ...
0
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2answers
267 views

How to sketch the spectrum of \$m(t) = \cos(1000)t \times \cos(3000)t\$

I know how to sketch the spectrum of \$m(t) = \cos(1000)t + \cos (3000)t\$ But I stack with that....when it's multiplied? How to sketch the spectrum \$m(t) = \cos(1000)t \times \cos(3000)t\$?
3
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1answer
260 views

Power supply noise measurements

Im working on a project where I need characterise the noise from a power supply so I can then design some filters. The power supply provides 5V, 12V and -12V to a set of analogue sensors (hence the ...
0
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1answer
90 views

How to listen to radio communications from a transmitter?

I have two devices communicating at a frequency which I don't know. I want to listen to that communication so that I can replicate one of the devices and fool the other. Basically I want to reverse ...
0
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1answer
566 views

RGB LED audio spectrum analyzer - Bandpass or FFT?

I'm about to build a coffee table which has a RGB LED matrix build in it just like in this video. https://www.youtube.com/watch?v=4NJDgvV8RZw I want the matrix to display an audio spectrum that ...
0
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1answer
49 views

What's the correlation between spectral graphs produced using near field probes and ones produced using an antenna?

I've been looking at getting some equipment for EMC-precompliance on a budget (about £5k). I understand that I can get a spectrum analyser with some EMI options and some near-field probes (about £2k) ...
0
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2answers
71 views

Best Sensor for obtaining types of objects at a distance

I could not completely describe the sensor required in the title, what I am looking for is a sensor that can pick up if there is a different material, from a preconfigured material type, lets say in ...
6
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2answers
425 views

Observing effect of household appliances on powerline communication

I had been recently working on Powerline communication modems (PLC). I put two PLC modems at different parts of my home and observed the data transfer rate between them. However, I observed that when ...
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2answers
2k views

Reading S2P Files - What Does Each Column Represent

I'm having a hard time reading s2p files. For an example say that I am measuring the parameters of a 2-port network (port 1 and port 2). What do each columns represent? I can tell that the first ...
2
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1answer
359 views

RF Harmonics and Spectrum Analysers

Please forgive the long question. I have split it into 2 parts. I am very confused about how harmonic suppression is measured in RF system (in my case, ham radios). I have picked up a couple of the ...
2
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1answer
152 views

Spectrum Analyzer vs. numerical FFT-based methods?

We sample a signal over time (e.g. voltage fluctuations of a resistor). Then do a FFT-based Power Spectral Density in a PC. What advantage would a physical spectrum analyzer provide over doing the ...
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1answer
741 views

Combine two signals of different frequencies in a test setup

I have a device that is powered from a current source. The current source supplies 10A at 60Hz - the magnitude is roughly 5-10VPP. I would like to inject another signal on top of that to simulate ...
2
votes
2answers
263 views

Can an oscilloscope add a frequency component to my signal?

I want to check the spectrum of a DDS signal ("pure" sinewave) for undesired frequency components. The way I am doing it is by storing the waveform from a 2GS/s oscilloscope (Agilent DSO81204) and ...
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3answers
3k views

What power is measured by a spectrum analyzer?

Is the signal level that is shown in a spectrum analyzer power of the signal being measured. If yes then what power is it: average power, true power or peak power? Also when using a power meter for ...
7
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1answer
292 views

What does sequences like 1-3, 1-10, 1-3-10 etc in a spectrum analyzer mean?

I have read in a paper explaining spectrum analyzer basic 'When selecting the RBW(resolution BW), there is usually a 1-10 or a 1-3-10 sequence of RBWs available. More RBWs are better because this ...
0
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1answer
105 views

Spectrum analyzer [closed]

Do we need to connect different frequency sine wave sources to spectrum analyzer? Or will spectrum analyzer supply different frequencies of sine wave source to the DUT? Could someone explain the basic ...
0
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2answers
145 views

Choosing Oscilloscope with appropriate bandwidth for Jitter analysis

Can someone give me a rule of thumb of choosing Oscilloscope with appropriate bandwidth for the Jitter analysis of clock signals? What device is highly preferable: spectrum analyzers, frequency ...
31
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2answers
2k views

Can anyone explain this high-frequency “alien voodoo black magic”?

I was casually watching Mike tear down a spectrum analyser (13:30 is the relevant part, 16:50 is the awesome part), and he came across what he aptly described as "weird messed up alien voodoo black ...
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2answers
400 views

Measuring Power per Hertz of a RF signal

I am testing my communication application to see it's performance over different frequencies. So I need to measure power at different frequencies of operation. I have been told that my limitation for ...
3
votes
1answer
182 views

finding rf 175 Mhz harmonic source

I have a device that I am pre testing to find possible issues with unintentional rf radation. The processor is a pic32 running at 80MHz, and is connected to a ti dp83848 ethernet phy in mii mode ...
3
votes
1answer
2k views

Disabling the camera auto white balance

I've decided to use standard web-camera as a simple spectrograph, being inspired by this website (and this one too). The device actually works, as you may see on the image: But you may see on the ...
1
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1answer
741 views

Building a cheap and stable microwave network analyser or oscillator (2-5GHz)

I am interested in measuring the changing dielectric constant of a liquid as it undergoes a process. My background research of scientific articles shows that the 2-5GHz range provides the best ...
2
votes
2answers
182 views

Does it make sense to plot the angle in an signal spectrum analyzer?

I've built a toy oscilloscope with an Arduino, acquiring the samples with the ADC and plotting the spectrum on my computer. The spectrum is the output of the FFT algorithm. You can see a video here of ...
2
votes
3answers
340 views

Spectrum Analyzer: Resolution Bandwidth vs Acquisition Time

Why a smaller resolution bandwidth (RBW) in a swept tuned spectrum analyzer RBW requires longer acquisition time?
3
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2answers
290 views

FCC verification and analyzer choice

I am in the design stage of a control surface that controls a remote audio DSP through ethernet. My plan is to target FCC 15 class A. The processor is a pic32 running at 80mhz. First question, what ...
10
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4answers
12k views

Oscilloscope with FFT or a Spectrum Analyzer?

Could someone explain to me please which aplications demand one and the other and why? As far as I read it's all about the 'db', is it true? And why? EDIT: Ok, I just read this question again, and ...
0
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1answer
131 views

Input impedance of a GenRad 2512 Spectrum Analyzer [closed]

Does anyone know the input impedance on the General Radio Model 2512 Spectrum Analyzer?
0
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2answers
237 views

Generic Active Probes

I need an active probe for use with a spectrum analyzer and oscilloscope. My scope has contacts around the BNC connector for powering a compatible probe. The spectrum analyzer is a different story. ...
1
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2answers
719 views

how to use a spectrum analyzer?

This is a new topic to me so it would be great if someone could give me a few pointers. I have an amplifier that I would like to get the frequency response for and a spectrum analyser with Probes A, ...
0
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1answer
131 views

Do comercial spectrum analyzers show a single-sided spectrum?

If I use a Bessell function to compute sidelobe power - do I need to double this power to get the power I will read on the specan?
2
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3answers
1k views

Designing a Audio Spectrum Analyzer

I want to design a simple LED audio spectrum analyzer kinda like this. Which method would be less expensive to do: Use many filters for each frequency band, depending on how much bands and LEDS I ...
4
votes
2answers
250 views

What's a good spectrum analyzer to learn with?

I'm trying to learn more about building RF circuits and I want to buy a spectrum analyzer. I've looked around on ebay, and a lot of them are really expensive. I'm a student, so I don't have a lot of ...
4
votes
2answers
434 views

What's the cheapest way to do basic EMI testing?

I need to test that my project will not interfere with radios in the 27 - 72 MHz band. I can't afford a spectrum analyser. Nor can I afford to buy all tx/rx pairs in between 27 and 72 MHz (27, 35, ...